document.write( "Question 124692: The sum of two numbers is 29. Their difference is 7. What are the two numbers \n" ); document.write( "
Algebra.Com's Answer #91403 by jim_thompson5910(35256)\"\" \"About 
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The sentence \"The sum of two numbers is 29\" translates to the equation \"x%2By=29\"\r
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\n" ); document.write( "\n" ); document.write( "The sentence \"Their difference is 7\" translates to the equation \"x-y=7\"\r
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\n" ); document.write( "\n" ); document.write( "Start with the given system of equations:\r
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\n" ); document.write( "\n" ); document.write( "\"system%28x%2By=29%2Cx-y=7%29\"\r
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\n" ); document.write( "\n" ); document.write( "Now in order to solve this system by using substitution, we need to solve (or isolate) one variable. I'm going to solve for y.\r
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\n" ); document.write( "\n" ); document.write( "So let's isolate y in the first equation\r
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\n" ); document.write( "\n" ); document.write( "\"x%2By=29\" Start with the first equation\r
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\n" ); document.write( "\n" ); document.write( "\"y=29-x\" Subtract \"x\" from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"y=-x%2B29\" Rearrange the equation\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-x%2B29%29%2F%281%29\" Divide both sides by \"1\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28%28-1%29%2F%281%29%29x%2B%2829%29%2F%281%29\" Break up the fraction\r
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\n" ); document.write( "\n" ); document.write( "\"y=-x%2B29\" Reduce\r
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\n" ); document.write( "\n" ); document.write( "Since \"y=-x%2B29\", we can now replace each \"y\" in the second equation with \"-x%2B29\" to solve for \"x\"\r
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\n" ); document.write( "\n" ); document.write( "\"x-highlight%28%28-x%2B29%29%29=7\" Plug in \"y=-x%2B29\" into the first equation. In other words, replace each \"y\" with \"-x%2B29\". Notice we've eliminated the \"y\" variables. So we now have a simple equation with one unknown.\r
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\n" ); document.write( "\n" ); document.write( "\"x%2Bx-29=7\" Distribute the negative\r
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\n" ); document.write( "\n" ); document.write( "\"2x-29=7\" Combine like terms on the left side\r
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\n" ); document.write( "\n" ); document.write( "\"2x=7%2B29\"Add 29 to both sides\r
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\n" ); document.write( "\n" ); document.write( "\"2x=36\" Combine like terms on the right side\r
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\n" ); document.write( "\n" ); document.write( "\"x=%2836%29%2F%282%29\" Divide both sides by 2 to isolate x\r
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\n" ); document.write( "\n" ); document.write( "\"x=18\" Divide\r
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\n" ); document.write( "\n" ); document.write( "-----------------First Answer------------------------------\r
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\n" ); document.write( "\n" ); document.write( "So the first part of our answer is: \"x=18\"\r
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\n" ); document.write( "\n" ); document.write( "Since we know that \"x=18\" we can plug it into the equation \"y=-x%2B29\" (remember we previously solved for \"y\" in the first equation).\r
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\n" ); document.write( "\n" ); document.write( "\"y=-x%2B29\" Start with the equation where \"y\" was previously isolated.\r
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\n" ); document.write( "\n" ); document.write( "\"y=-%2818%29%2B29\" Plug in \"x=18\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=-18%2B29\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"y=11\" Combine like terms \r
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\n" ); document.write( "\n" ); document.write( "-----------------Second Answer------------------------------\r
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\n" ); document.write( "\n" ); document.write( "So the second part of our answer is: \"y=11\"\r
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\n" ); document.write( "\n" ); document.write( "-----------------Summary------------------------------\r
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\n" ); document.write( "\n" ); document.write( "So our answers are:\r
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\n" ); document.write( "\n" ); document.write( "\"x=18\" and \"y=11\"\r
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\n" ); document.write( "\n" ); document.write( "which form the point \r
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\n" ); document.write( "\n" ); document.write( "So the two numbers are 18 and 11
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